208 - Mega Steelix by Tails19950 on deviantART

Onix (Pokémon GO): Stats, Moves, Counters, Evolution

Pokémon Omega Ruby and Alpha Sapphire add Mega-Evolutions for Steelix, Glalie - Polygon

Every time a Pokemon is Mega evolved, its regular Pokedex entry # Seen goes up by 1 but Caught stays the same. : r/TheSilphRoad

Elite Trainer Mark on X: Onix was Brock's first ever Pokémon. However, it didn't even evolve under his ownership, it evolved into Steelix while his brother Forrest was taking care of it.

What is a mega evolution in Pokémon? - Quora

1 x Mega-Steelix-EX - 109/144 - Full Art Ultra Rare Pokemon XY - Steam Siege

Brand New Factory Sealed Mega Construx Pokemon Squirtle Evolution Set (379 Pcs)

Darwinian Mega Evolution: pinser to houndoom

How to collect special items in Pokémon Go Gen 2: Evolving Onix into Steelix

Pokémon Go Metal Coat - evolve Scyther into Scizor, Onix into Steelix, and how to get the Metal Coat